I've been reading up on ESA's Vega rocket and was wondering whether it might be a good idea to use it as a launcher for a small manned craft as it appears that ESA will probably not be working with the Russians on Kliper.

I believe the first stage is based on an Ariane SRB and all the other stages rely on solid propellants also. According to Astronautix the final stage also has liquid fueled engines for fine adjustment.

Because Vega is at a relatively early stage in development any design changes required for man-rating could be included now rather than retrofitted later at greater cost.

A craft could use some of the equipment being designed for the ATV for docking and guidance.

The payload for it is quoted as being 1,500kg to a 700km circular orbit so I guess it could put something like 2,000kg to the ISS.

It should be possible to build a relatively simple 2 or 3 man vehicle at this weight. I couldn't find what the launch cost of Vega will be but I suppose it will be around the $60m mark which makes it much cheaper than an Ariane launch.

I think that the current craft designs are to large and heavy, Mercury and Gemini were probably light enough to launch on Vega, so it should be possible to create a modern capsul with much more functionality at this weight.

What do you think, is this a goer? Would this be a better bet than using Ariane 5 or working with the Russians on Kliper?

_________________A journey of a thousand miles begins with a single step.

Gemini weighed nearly 4 tons, so thats far out of the Vega payload capability. Even if you consider "modern" material science and electronics I would say it's not possible to achieve 2 tons. Additionally I would guess that the acceleration is a bit high for manned transport.

edit:
I just reviewed the design manual. The highest acceleration is about 6.2g (5.5 static+0.7 dynamic acceleration), that's a lot more than for example for the shuttle (as far as I remember 3g). The payload for 400km, 51° inclination is around 2050kg according to the design manual (had to interpolate, the drawings showed only 300km and 500km so I would say they don't even consider to fly to the ISS *g*)

The reentry module mass is given as 1983kg, with a breakdown of the various component weights. Looking at the list I would have thought that it would be possible to save a s lot of weight using modern materials and electronics. The crew seats and provisions account for 426kg of this total alone. Assuming you could reduce the overall mass by a third (I know this is a big assumption but I think that it is possible) this would allow about 700kg for a propulsion module and docking mechanism which could be allowed to reenter separately and burn up.

Still seems doable to me.

With regard to pulling 6gs other threads are talking about up to 18 so it appears some people are willing to turn themselves into pancakes to get into orbit. I haven't seen the launch profile for Vega, how long would someone have to put up with 6gs? If this was a problem then perhaps the solid fuel could be altered to burn for longer and give slightly less thrust. I didn't have in mind using this for the general public so hopefully the crew would be fairly used to experiencing such stresses.

_________________A journey of a thousand miles begins with a single step.

Gemini was able to use ejection seats because of the 2 doors built into the capsule, these were done away with on Apollo and the shuttle so I had not intended to use them on Vega. A LES system incorporated in the upper stage (maybe even making it possible for the upper stage itself to provide the thrust to get the capsule clear of the rest of the launcher).

This should save weight on the seats and removing the doors should reduce the capsule's weight and make it stronger.

If I read the graphs right it seems like Vega accelerates at a constant rate for about 5 minutes, which could be a problem. Not sure what the limits or acceptable loads are on crew during a launch.

_________________A journey of a thousand miles begins with a single step.

Don't you think that Ariane 5 is more suitable for manned spaceflights in Europe?

Yes but Ariane 5 would lead to a Hermes sized craft (that was why it was originally designed after all) and I doubt very much that ESA will be willing to go down that route again. My thinking was to start smaller and cheaper with Vega and create some infrastructure, experience and public interest at a lower cost than the full scale Ariane craft would mean.

From Klaus's earlier post it seems Vega is expected to cost about $20m a launch, about a tenth of an Ariane launch. ESA might be willing to fund a small scale vehicle based on Vega (they considered spending $60m on a study for Kliper), I think it highly unlikely that an Ariane based manned craft would be even considered.

IT is also probably easier to design and build a smaller craft due to stresses and re-entry temperatures.

If things worked out then the craft could always be scaled up later when manned spaceflight was more accepted in Europe. Also such a vehicle could be used on other launch systems as it would not require such a large booster and might be able to be sold to other countries like the US for instance to fill the Soyuz-CEV gap. This approach also would create competition for the Russians and keep Soyuz/Kliper prices from climbing higher.

This makes quite a bit of sense if you think about it, all other manned space programs have started with a single astronaut vehicle why should Europe be any different? Where no capability exists you start small and grow you do not start with a large craft. This is the progression that China is making at the moment and the one that the US and Russia followed in the 50s and 60s.

I think in the case of ESA it is possible to stretch from a single to a 2 man craft because of the experience with unmanned launches but any further is probably over reaching at the moment.

_________________A journey of a thousand miles begins with a single step.

Cant see the French leaving ESA with the amount of money and time they have invested in Arianne.

I think that within the next few years, 5 at most, ESA will have to start to develop its own manned craft. The reason for this will be its credibility.

With agencies like ISRO talking about having a manned space program how can ESA say that it is in the same league as NASA or the Russians without a vehicle of its own. If it doesnt do something relatively quickly it will find itself held hostage to the Russians for flights to the ISS and the price is likely to rise.

It is the next logical step in the Aurora program. How is it supposed to mount a manned Mars mission without one?

_________________A journey of a thousand miles begins with a single step.

Ariane 5 would be a near-perfect fit for CEV though. A big simple capsule is what the Ariane-5 class Saturn 1B launched during ASTP after all. Vega seems a bit small and you have to ask yourself what it offers in the way of transport to ISS, its fuel load, etc.

The Stick is a good CEV booster, but Vega may very well be too small for anything other than a simple Mercury type launch, if that.

I agree that long term Vega will not cut it as a crew transport but we are talking about gaining experience and virtually starting from scratch. I guess it depends though on how much payload Vega could conceivably carry, a couple of side boosters might give enough extra kgs to make it worth pursuing. The cost is the real driver though, ESA could have something operating at a fraction of the cost on par with the Russians Soyuz, it couldn't achieve that with Arianne.

I like the idea of Arianne for the CEV but I dont see NASA using anything but a home grown US launcher and spending the necessary billions on development. The best that I could see happening is making the CEV lauchable off of a number of different boosters one of which could be Arianne.

_________________A journey of a thousand miles begins with a single step.

Cant see the French leaving ESA with the amount of money and time they have invested in Arianne.

I think that within the next few years, 5 at most, ESA will have to start to develop its own manned craft. The reason for this will be its credibility.

With agencies like ISRO talking about having a manned space program how can ESA say that it is in the same league as NASA or the Russians without a vehicle of its own. If it doesnt do something relatively quickly it will find itself held hostage to the Russians for flights to the ISS and the price is likely to rise.

It is the next logical step in the Aurora program. How is it supposed to mount a manned Mars mission without one?

There were rumors and indications that France considers leaving the ESA because of their discontent with ESA policy. For example they are extremly unsatisfied with the Italian Vega launcher. And as the plan for Kliper cooperation is cancelled they might consider to cooperate with Russia themselves. They always had very good relations (especially space-related) to Russia.

edit:
ESA already has a bit of "capsule" knowledge. They once launched the ARD (as far as I remember Atmospheric Reentry Demonstrator)with an Ariane 5.

There were rumors and indications that France considers leaving the ESA because of their discontent with ESA policy. For example they are extremly unsatisfied with the Italian Vega launcher. And as the plan for Kliper cooperation is cancelled they might consider to cooperate with Russia themselves. They always had very good relations (especially space-related) to Russia.

edit:ESA already has a bit of "capsule" knowledge. They once launched the ARD (as far as I remember Atmospheric Reentry Demonstrator)with an Ariane 5.

Yes thats true they developed ARD, there are some links under the Financial Barriers section in the "smaller cheaper spacecraft" thread.

I hadn't heard about the French being disatisfied with ESA, where did you hear that?

_________________A journey of a thousand miles begins with a single step.